System of electrical control.



P. H. THOMAS.

SYSTEM OF ELECTRICAL CONTROL.

APPLICATION FILED JUNE 19, 1906.

91 6,223 Patented Mar. 23, 1909.

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SYSTEM OF ELECTRICAL CONTROL.

APPLICATION FILED JUNE 19, 1905.

91 6,223. Patented Mar. 23, 1909.

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PEBCY H. THOMAS, OF EAST ORANGE, NEW .IERSEY, ASSIGNOR TO COOPER HEWITT ELECTRIC COMPANY, OF NEW YORK, N. Y.,

A CORPORATION OF NEW YORK.

SYSTEM OF ELECTRICAL CONTROL.

Specification of Letters Patent. Patented March 28, 1909.

Application filed June 19, 1906. Serial No. 266,888.

To all whom it may concern:

Be it known that I, PERCY H. THOMAS, acitizen of the United States, andresident of East Orange, county of Essex, State of'New Jersey, have invented certain new and use- .ful Im rovements in Systems of Electrical the property of maintaining across its termi- States main constant.

itself varied at will. s one means nals an approximately constant voltage independent of the current voltage. By usin such a device, the subtraction of potential from the supply circuit before it is delivered to the work circuit is a constant factor provided the conditions in the va or device re- It is known, owever, that the constant otential which is thusmaintained upon the terminals of the vapor a paratus is de endent upon the length of t e vapor path, t at is to say, upon the distance between the'positive electro e and the point at which the current enters the negative electrode. Byyar'ying, then, the length of the vapor path, the voltage which is to be subtracted from the su ply voltage may be for ad- 'usting the length-of the vapor path, it has con ire osed to tilt the vapor device so that t e iquid' positiveelectrode might be brought nearer to or arther away from the fixed positive electrode. There is, of course, no inherent reason why both electrodes should not be movable nor why the movement of the container. of thev device should not act upon both electrodes to move them nearer together or farther apart. Another means for accomplishing the same result consists of a movable magnet which by its position determines the point at which the current traversing the device shall enter the negative electrode, thereby determining the length of the vapor path traversed by the current. This function of a magnet for determining-the entrance point of current to the negative electrode is described in United atent No. 7 49,7 93 issued January 19,-

1=904 to Peter Cooper Hewitt.

So faras I am aware, the apphcatlon of the-vapor device in-the manner described has heretofore current work.

templates the appllcat on of the. same apbeen suggested only for direct The present invention conparatus and the same principle of operation to alternating current circuits. For eonvenience, connection with a varying speed motor supplied with direct current from an alternating current source. Two modes of embodying shown inh igures 1 and 2 of the drawings.

Referring to the first figure of the drawing, 1 and 2 are electric mains supplied with current from an alternating current source, 3 and 4 are, respectively, the field magnet and from the said mains. One terminal of the said motor is connected with an intermediate point on an induction device, 5, connected between the said mains, while the other ter- 6, of a "vapor device, 7. The two positive electrodes, 8 and 9, of the said vapor device are connected by wires 10 and 11, respectively, with the mains 2 and 1.

The organization thus far described is capable of transmitting through the vapor .device 7 to the electric motor 3-4. a direct current capable of operating the same. To vary the speed of the motor a clamping arm, 12, pivoted at 13 and supporting the vapor devlce 7 may be turned upon its pivot by means of a handle, 14, so as to bring the mercury constituting the negative electrode 6 into closer or more remote relation to the ositive electrodes 8 and 9, thus varying the ength of the vapor column at will. In Fig. 1 the same result is accomplished by the use of a movable magnet, 15, mounted on wheels or rollers, 16, or otherwise made adjustable along the entire length of the mercury electrode 6. Inasmuch as the position of the magnet 15 determines the point at which the current traversing the vapor device 7 enters the negative electrode, it is manifest that the length of the vapor column is subject to ready control.

It will be understood that while the regulatiori herein described applies primarily to the use of a variable vapor resistance controlling alternating current circuits, yet some of the features of the invention relate not only to adeviee applied to such a use but to a vopor device connected to a work whether alternating or direct. I claim as my invention 1. In a system of electrical distribution I have illustrated the device in this principle are illustrated in the diagrams.

armature of a direct current motor supplied minal is connected to the negative electrode fier com the combination with a work circuit and an alternating current supply, of a vapor rectifier comprising an hermetically sealed and completely exhausted container and suitable electrodes therei'or, one of which is a vaporizable reconstructing cathode, said rectifier supplying direct current to said work circuit from said supply, together with means whereby the vapor column of said rectifier may be given different effective lengths independent of the current flowing.

2. In a system of electrical distribution the combination with a work circuit and an alternating current supply, of a vapor rectirising an hermetically sealed and complete 1 exhausted container, including a plurality of anodes and a vaporizable reconstructing cathode, said reetlfier delivering direct current to said work circuit from said alternating supply, together with means whereby the length of the vapor path between the several anodes and a cathode may electrodes therefor, one of which is a vaporizable reconstructing'cathode, said rectifier supplying direct current to said work circuit from said supply, together with means whereby the said rectifier may be tilted to give different eflective lengths of vapor column independent of the current flowing.

Signed at New York, in the county of ew York, and State of New York, this 15th day of June, A. D. 1905.

PERCY l-I. THOMAS.

Witnesses: 7 WM. H. CAPEL, GEORGE H. SrooKBRmeE. 

